Description: (Applicant's Description) A program to access potentially useful anticancer compounds from filamentous fungi is described. The fungi will be selected based on ecological principles that stress and interactions with other organisms enhance secondary metabolite production. Fungi that are closely associated with plants (especially endophytic fungi) or with insects (especially entomopathogenic fungi) will fulfill the interacting with other organisms criteria. The specific aims are: Provide 100 fungal cultures per month to W-AR for culturing and screening. Isolates will come from the USDA/ ARS Entomopathogenic Fungi collection or the eco-taxanomic collection at UC, Berkeley. All fungal samples will have at least preliminary taxonomy. Perform bioassay-guided isolation of active constituents and provide purified compounds for further biological evaluation. Determine the molecular structures of biologically active constituents. Develop molecular genetic probes for natural product biosynthesis.